TATA Box-Binding Protein (TBP)-Related Factor 2 (TRF2), a Third Member of the TBP Family

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 96; no. 9; pp. 4791 - 4796
• Main Authors: Rabenstein, Mark D., Zhou, Sharleen, Lis, John T., Tjian, Robert
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences of the United States of America 27.04.1999; National Acad Sciences; National Academy of Sciences; The National Academy of Sciences
• Subjects: Actins; Amino Acid Sequence; Animals; Antibodies; Biochemistry; Biological Sciences; Caenorhabditis elegans; Chromosome Mapping; Cloning, Molecular; DNA-Binding Proteins - genetics; Drosophila; Drosophila melanogaster; Family members; Gene expression regulation; Genes; Genetic loci; Humans; Molecular Sequence Data; Proteins; Sequence Alignment; Sequence Analysis; TATA Box; Telomeric Repeat Binding Protein 2; Testes; Transcription, Genetic
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.96.9.4791

The TATA box-binding protein (TBP) is an essential component of the RNA polymerase II transcription apparatus in eukaryotic cells. Until recently, it was thought that the general transcriptional machinery was largely invariant and relied on a single TBP, whereas a large and diverse collection of activators and repressors were primarily responsible for imparting specificity to transcription initiation. However, it now appears that the "basal" transcriptional machinery also contributes to specificity via tissue-specific versions of TBP-associated factors as well as a tissue-specific TBP-related factor (TRF1) responsible for gene selectivity in Drosophila. Here we report the cloning of a TBP-related factor (TRF2) that is found in humans, Drosophila, Caenorhabditis elegans, and other metazoans. Like TRF1 and TBP, TRF2 binds transcription factor IIA (TFIIA) and TFIIB and appears to be part of a larger protein complex. TRF2's primary amino acid structure suggests divergence in the putative DNA binding domain, and not surprisingly, it fails to bind to DNA containing canonical TATA boxes. Most importantly, TRF2 is associated with loci on Drosophila chromosomes distinct from either TBP or TRF1, so it may have different promoter specificity and regulate a select subset of genes. These findings suggest that metazoans have evolved multiple TBPs to accommodate the vast increase in genes and expression patterns during development and cellular differentiation.